Method and apparatus for recharging batteries in a more efficient manner

ABSTRACT

A battery charger including a converter unit, a terminal adaptor, a cable, a battery, and/or multiple power connectors. A terminal, such as an electronic device, can be connected to the converter unit using the cable or directly to the converter unit without the cable. The converter unit determines when to draw power from an external power and when to cease drawing power from the external power source by detecting a power enablement condition or a power disablement condition. The power disablement condition occurs when the terminal is fully charged, the terminal is disconnected from the converter unit, and/or a charge time of the terminal exceeds the predetermined charge time threshold. The power enablement condition occurs when the terminal is initially connected to the converter unit and/or the terminal needs to be charged. The battery supplies power to components of the converter unit and/or the terminal.

RELATED APPLICATIONS

The present application is a continuation of prior application Ser. No.13/649,004, filed Oct. 10, 2012, which is a continuation of applicationSer. No. 12/607,946, filed Oct. 28, 2009, the entire disclosure of theseapplications being incorporated herein by reference.

BACKGROUND

1. Field of the Invention

The present invention relates to a method and apparatus for rechargingbatteries in a more efficient manner, and more specifically to a methodand apparatus for optimizing the operational and down time of chargersor power supplies.

2. Description of the Related Art

A conventional battery charger has one end connected to a power sourceand another end connected to an electronic device. The conventionalbattery charger draws power from the power source to supply to theelectronic device. However, the conventional battery charger can drawpower from the power source even when the electronic device isdisconnected, or fully charged. In some situations, the excessconsumption can be, for example, 15 mW or more. With the millions ofpower adapters in use today, this translates into a large amount ofwasted energy and a negative effect on the environment.

Thus, there is a need for a method and apparatus for optimizing theoperational and down time of chargers or power supplies.

SUMMARY

In one embodiment, the present invention includes a method and apparatusfor optimizing the operational and down time of chargers or powersupplies. A battery charger includes a converter unit and a cable. Aterminal, such as an electronic device, can be connected to theconverter unit using the cable or directly to the converter unit withoutthe cable. The converter unit can determine when to draw power from anexternal power source and when to cease drawing power from the externalpower source by detecting a power enablement condition or a powerdisablement condition.

The power disablement condition can occur, for example, when theterminal is fully charged, the terminal is disconnected from theconverter unit, and/or a charge time of the terminal exceeds thepredetermined charge time threshold. This reduces an amount of powerdrawn by the battery charger when it would not be productive to bedrawing power from the external power source. The converter unit canalso periodically wake-up to monitor the terminal to determine whetherthe power disablement condition still exists. The power enablementcondition can occur, for example, when the terminal is initiallyconnected to the converter unit and/or the terminal needs to be charged.This allows the terminal to still be appropriately charged even whenconserving energy.

The converter unit can also include a battery to supply power tocomponents of the converter unit and/or the terminal when the converterunit ceases drawing power from the external power source. Thus, amonitoring function in the battery charger can remain functional evenwhen it does not receive power from the external power source.Furthermore, the converter unit can also include a power input includingmultiple power connectors. This allows the power connector to receivepower from a variety of power sources.

In one embodiment, the present invention includes an electric chargecutoff device including a terminal adapter connectable to a terminal, acable connected to the terminal adapter, a power connector for receivingpower from a power source, and a sensor circuit electrically coupledbetween the power source and the cable. The sensor circuit connects thecable to the power connector when a change in capacitance is detectedfrom the cable or the terminal adapter is connected to the terminal. Thesensor circuit can also optionally disconnect the cable from the powerconnector when no capacitance has been detected from the cable.

In another embodiment, the present invention is a battery chargerincluding a converter unit connectable to a terminal and an externalpower source, wherein the converter unit disables reception of powerfrom the external power source and disables a supply of power to theterminal when the converter unit detects a power disablement condition.

In yet another embodiment, the present invention is a battery chargerincluding a latched relay connectable to an external power source,wherein the latched relay disables reception of power from the externalpower supply when a power disablement condition occurs and enablesreception of power from the external power supply when a powerenablement condition occurs, and a load monitor circuit connectable to aterminal, the load monitor circuit detecting when the load monitorcircuit is electrically connected to the terminal and supplying power tothe terminal when the power enablement condition occurs.

In still another embodiment, the present invention is a method forcharging a battery including detecting when a terminal is connected to aconverter unit, detecting a power disablement condition, disablingreception of power from an external power source when the powerdisablement condition is detected, and disabling a supply of power tothe terminal when the power disablement condition is detected.

BRIEF DESCRIPTION OF THE DRAWINGS

The features, obstacles, and advantages of the present invention willbecome more apparent from the detailed description set forth below whentaken in conjunction with the drawings, wherein:

FIG. 1 is a block diagram of a battery charger according to anembodiment of the present invention;

FIG. 2 is a perspective view of a battery charger according to anembodiment of the present invention;

FIG. 3 is a sliced view of a cable according to an embodiment of thepresent invention;

FIG. 4 is a circuit diagram of a portion of a converter unit accordingto an embodiment of the present invention;

FIG. 5 is a circuit diagram of a portion of a converter unit accordingto an embodiment of the present invention;

FIG. 6 is a circuit diagram of a portion of a converter unit accordingto an embodiment of the present invention;

FIG. 7 is a circuit diagram of a portion of a converter unit accordingto an embodiment of the present invention; and

FIG. 8 is a flow chart of a process according to an embodiment of thepresent invention.

DETAILED DESCRIPTION

Apparatus, systems and methods that implement the embodiments of thevarious features of the present invention will now be described withreference to the drawings. The drawings and the associated descriptionsare provided to illustrate some embodiments of the present invention andnot to limit the scope of the present invention. Throughout thedrawings, reference numbers are re-used to indicate correspondencebetween referenced elements.

FIG. 1 is a block diagram of a battery charger 100, while FIG. 2 is aperspective view of the battery charger. The battery charger 100includes, for example, a converter unit 102, a cable 104, a terminal106, and/or a main voltage input 118.

The terminal 106 is connected to the cable 104 and can be an electronicdevice. The terminal 106 can be, for example, a music player, a cellphone, a laptop, a desktop computer, a personal digital assistant (PDA),a camera, or any other type of electronic device which includes arechargeable battery. In one embodiment, the converter unit 102transmits power from the cable 104 to charge the terminal 106.

The cable 104 is connected to the converter unit 102 and the terminal106. The cable 104 transmits power and/or information between theconverter unit 102 and the terminal 106. The cable 104 can be any typeof cable that can transmit power and/or information between theconverter unit 102 and the terminal 106. The terminal 106 can beconnected to the cable 104 using a terminal adapter 107 (FIG. 2). Theterminal adapter 107 can be, for example, a universal serial bus (USB)adapter, an IEEE 1394 interface, a proprietary adapter specific to aterminal, or any other type of adaptor that can be used to charge therechargeable battery in the terminal.

FIG. 3 depicts the cable 104 at a plane perpendicular to an axialdirection of the cable 104. As seen in FIG. 3, the cable 104 includes anouter shell 132 and a conductive material 134. The outer shell 132 canbe formed, in part, from an insulating material such as plastic orrubber or any other type of insulating material. The conductive material134 can be, for example, a copper based wire or any other type ofconductive material. The conductive material 134 can transmit the powerand/or information between the convert unit 102 and the terminal 106,while the outer shell 132 can insulate the conductive material 134 fromoutside elements.

The cable 104 can also have a capacitance, which will increase, forexample, when a user touches or is touching the cable 104. Thecapacitance can be, for example, a capacitance of the outer shell 132.Thus, if a user touches the outer shell 132, for example, with twofingers, the capacitance of the outer shell 132 can increase. When theuser touches the outer shell 132, a small current can flow through theuser, increasing the capacitance of the outer shell 132. The capacitanceof the cable 104 can be used, for example, to determine whether theterminal 106 is connected to the converter unit 102, which will bedescribed later. Although FIG. 1 and FIG. 2 depict the use of the cable104, the terminal 106 can also connect directly to the converter unit102.

The main voltage input 118 is connected to the converter unit 102 and isconnectable to an external power source. The main voltage input 118 canbe, for example, a variety of power inputs such as a DC plug 118 aand/or an AC plug 118 b. The main voltage input 118 can be connected toan external power source and draw power from the external power source.The main voltage input 118 can also be any type of power connector thatcan receive power from the external power source. For example, the DCplug 118 a can be connected to a DC outlet, such as a 12 V DC outlet, inan automobile. The AC plug 118 b, for example, can be connected to anelectrical socket, such as a 110 V or 120 V socket, in a conventionalhouse. Although the main voltage input 118 includes the AC plug 118 aand the DC plug 118 b, the main voltage input 118 can include any numberof power connectors.

The DC plug 118 a and the AC plug 118 b can also be placed in variouspositions depending on whether each of the components is in a storagemode or an active mode. This allows for the compact storage of thebattery charger 100 when not in use, but allows the battery charger 100to retain its functionality when it is ready for use.

The DC plug 118 a can remain in a first position, such as a storedposition, when the DC plug 118 a is not in use and in a storage mode.The DC plug 118 a can rotate in a direction 126 to a second position,such as an active position, when ready for use and in the active mode.Likewise, the AC plug 118 b can remain in a first position, such as astored position, when not in use and in a storage mode. The AC plug 118b can, for example, rotate in a direction 124 to a second position, suchas an active position, when ready for use and in the active mode.

The converter unit 102 is connected to the cable 104 and/or the terminal106. The converter unit 102 can also be directly connected to theterminal 106 without the cable 104. As seen in FIG. 1, the converterunit 102 includes a microcontroller 108, a load monitor circuit 110, alatched relay 112, a battery monitor and charging circuit 114, a battery116, and a power supply 120.

The load monitor circuit 110 is connectable to the terminal 106 eitherdirectly or through the cable 104. The load monitor circuit 110 is alsoelectrically connected to the microcontroller 108, and/or the powersupply 120. The load monitor circuit 110 can include a sensor. Thesensor can detect whether the terminal 106 is electrically connected tothe converter unit 102. For example, the sensor can detect whether theterminal 106 is electrically connected to the load monitor circuit 110.

In one embodiment, to detect whether the terminal 106 is electricallyconnected to the battery charger 100, the sensor detects a capacitanceof the terminal 106. For example, when a mobile phone is connected tothe load monitor circuit, there will be an increase in capacitance.

In another embodiment, the sensor can detect whether the terminal 106 iselectrically connected to the load monitor circuit 110 by detecting acapacitance increase in the cable 104. The capacitance increase can becaused, for example, by a user touching the cable 104. When the usertouches the cable 104, it is likely that the user is connecting theterminal 106 to the battery charger 100 through, for example, the cable104. This can indicate that the terminal 106 will be electricallyconnected to the load monitor circuit 110.

The power supply 120 is connected to the main voltage input 118 and/orthe load monitor circuit 110. The power supply 120 is connected to themain voltage input 118 through a switch 119. The switch 119 can beconnected or disconnected. When the switch 119 is disconnected, no powerflows from the main voltage input 118 to the power supply 120. When theswitch 119 is connected, power flows from the main voltage input 118 tothe power supply 120. The power supply 120 can supply power to the loadmonitor circuit 110 and/or the terminal 106 when the switch 119 isconnected.

The battery 116 is electrically connected to the latched relay 112, themicrocontroller 118, and/or the power supply 120. The battery 116 canalso be electrically connected to the terminal 106, for example, throughthe microcontroller 108 and/or the power supply 120. The battery 116 cansupply power to the microcontroller 108 and/or the terminal 106.

The battery 116 can be charged by the external power source when theswitch 119 is connected and when the latched relay 112 enables power toflow to the battery 116. When the switch 119 is disconnected, and/or thelatched relay 112 disables power from flowing to the battery 116, thebattery 116 does not receive power from the external power source. Thebattery 116 can include, for example, a rechargeable battery 176, asuper capacitor (“supercap”) 178, and/or a solar cell 180. The battery116 can also include any other type of energy storage or renewableenergy device which can be used to power the microcontroller 108 and/orthe terminal 106. In one embodiment, the battery 116 can have anunlimited shelf life. Thus, the battery 116 can operate and hold for thelife of the battery charger 100. Therefore, the battery 116 does notneed to be replaced.

The battery monitor and charging circuit 114 is electrically connectedto the latched relay 112, the microcontroller 108, and/or the battery116. The battery monitor and charging circuit 114 can monitor an energylevel of the battery 116.

The latched relay 112 is electrically connected to the switch 119, thebattery 116, and/or the battery monitor and charging circuit 114. In oneembodiment, the switch 119 can be part of the latched relay 112. Thelatched relay 112 can connect or disconnect the switch 119. When theswitch 119 is disconnected, no power flows from the external powersource through the main voltage input 118 to the power supply 120. Whenthe switch 119 is connected, power can flow from the external powersource through the main voltage input 118 to the power supply 120.

In one embodiment, when the switch 119 is disconnected, the terminal 106is not charged. This is beneficial, for example, when the terminal 106is already fully charged. In such a case, energy is prevented from beingwasted by discontinuing the current flow from the external power source.The switch 119 can be positioned, for example, between the main voltageinput and any component that creates a loading, such as the power supply120. This allows the switch 119 to discontinue the current flow from theexternal power source to the terminal 106.

The latched relay 112 is electrically connected to the main voltageinput 118, the power supply 120, the battery 116, the battery monitorand charging circuit 114, and/or the microcontroller 108. The latchedrelay 112 is also electrically connected to the switch 119. The latchedrelay 112 can connect or disconnect the switch 119 based on instructionsfrom the microcontroller 108. The latched relay 112 can also enable ordisable the supply of power to the battery 116 based on the instructionsof the microcontroller 108.

The microcontroller 108 is electrically connected to the load monitorcircuit 110, the battery monitor and charging circuit 114, the latchedrelay 112, and/or the battery 116. The microcontroller 108 can receivepower from the external power source and/or the battery 116. Forexample, when the switch 119 is disconnected and the converter unit 100does not receive power from the external power source, the battery 116can supply power to the microcontroller 108. This allows themicrocontroller 108 to operate even when the external power source isnot supplying power to the converter unit 100. The microcontroller 108receives information regarding the energy level of the battery 116 fromthe battery monitor and charging circuit 114. When the energy level ofthe battery 116 is below a predetermined energy level threshold, thebattery 116 instructs the latched relay 112 to supply power to thebattery 116. This guarantees that the microcontroller 108 will alwayshave enough power to operate, even when the converter unit 102 isconserving energy by not drawing power from the external power source.

The microcontroller 108 can also detect a power disablement conditionand a power enablement condition. During a power disablement condition,the microcontroller 108 instructs the latched relay 112 to disconnectthe switch 119. By disconnecting the switch 119, power does not flowfrom the main voltage input 118 to the power supply 120, and theconverter unit 102 ceases drawing power from the external power supply.This saves power since much of the power that is drawn by a batterycharger during a power disablement condition is wasted.

The power disablement condition can be, for example, when the terminal106 is electrically connected to the converter unit 102 and is fullycharged. Thus, the microcontroller 108 can receive a signal from theload monitor circuit 110 indicating that the terminal 106 is connectedto the converter unit 102. The microcontroller 108 can then detect avoltage and/or current of the terminal 106.

In one embodiment, when the voltage of the terminal 106 exceeds apredetermined voltage threshold, then the terminal 106 is fully charged.For example, if the voltage of the terminal 106 is 21 volts, and thepredetermined voltage threshold is 20 volts, then the terminal 106 isfully charged. In another embodiment, when the current of the terminal106 is below a predetermined current threshold, then the terminal 106 isfully charged. For example, if the current of the terminal 106 is 50 mAand the predetermined current threshold is 60 mA, then the terminal 106is fully charged.

When the power disablement condition is detected, the microcontroller108 instructs the latched relay 112 to disconnect the switch 119. Oncethe switch 119 is disconnected, the converter unit 102 ceases drawingpower from the external power source, reducing energy consumption. Thus,the battery charger 100 does not draw power from the external powersource, even when the battery charger 100 is connected to the externalpower source. However, if the voltage of the terminal 106 is 18 volts,and/or the current of the terminal 106 is 70 mA, then the terminal 106is not fully charged, and there is no power disablement condition.

The power disablement condition can also be, for example, when a chargetime of the terminal 106 exceeds a predetermined charge time threshold.The microcontroller 108 can also determine that the terminal 106 isfully charged based on the charge time. In one embodiment, the chargetime can begin, for example, when the terminal 106 is initiallyconnected to the converter unit 102. In another embodiment, the chargetime can begin when the voltage of the terminal 106 remains stagnant fora predetermined period of time. By remaining stagnant for apredetermined period of time, the terminal 106 may be fully charged,even if the voltage does not exceed the predetermined voltage threshold.When the charge time begins, however, can be appropriately determinedbased on the terminal 106 or any other criteria. Once the charge timeexceeds the predetermined charge time threshold, the microcontroller 108instructs the latched relay 112 to disconnect the switch 119. Thisenables power conservation by preventing the converter unit 102 fromdrawing power when the terminal 106 is already full, nearly full, or hasalready been charged for an appropriate amount of time. Thus, even ifthe battery charger 100 is connected to the external power source, itdoes not draw power from the external power source.

The power disablement condition can also be, for example, when theterminal 106 is disconnected from the converter unit 102 and/or thebattery charger 100. Thus, when the load monitor circuit 110 sends asignal to the microcontroller 108 that the terminal 106 is disconnectedfrom the converter unit 102, the microcontroller 108 sends a signal tothe latched relay 112 to disconnect the switch 119. This disables powerreception by the battery charger 100 from the external power source evenif the battery charger 100 is connected to the external power source.

In power disablement situations, power consumption by the converter unit102 and/or the battery charger 100 does not perform any meaningfulfunction, such as by charging a terminal 106, since the terminal 106 isalready fully charged or disconnected from the converter unit 102 and/orthe battery charger 100. Thus, by ceasing drawing power from theexternal power source in power disablement situations, power consumptionof the converter unit 102 and/or the battery charger 100 can be reducedand efficiency of the converter unit 102 can be increased. For example,the user may not notice that the terminal 106 is fully charged. This isespecially prevalent where the user is, for example, charging theterminal 106 overnight while the user is sleeping.

The power enablement condition can be, for example, when the terminal106 is initially connected to the converter unit 102 and/or the batterycharger 100. During the power enablement condition, the microcontroller108 sends the signal to the latched relay 112 that the switch 119 shouldbe connected. This can, for example, allow the converter unit 102 todraw power from the external power source and to charge the terminal106.

In one embodiment, the power enablement condition can last for apredetermined time period even when the power disablement conditionoccurs. For example, if the electronic charger is fully charged wheninitially connected to the battery charger 100, the battery charger 100can still enable power from the external power source for thepredetermined time period. During the predetermined time period, themicrocontroller 108 can, for example, determine whether the terminal 106is full. In another embodiment, during the predetermined time period,the microcontroller 108 can determine if the disablement conditionoccurs and proceed with actions associated with the disablementcondition after the predetermined time period has elapsed.

In another embodiment, the converter unit 102 can periodically wake upfrom the power disablement condition to monitor the terminal 106. Theconverter unit 102 can determine whether the power disablement conditionstill exists and whether to continue disabling power reception from anexternal power source or disabling the supply of power to the terminal106. For example, the power enablement condition can occur when theterminal 106 is connected to the converter unit 102 and the powerdisablement time exceeds a predetermined power disablement timethreshold. The power disablement time can commence when the powerdisablement condition is detected. For example, when the microcontroller108 determines that the power disablement condition occurs, the powerdisablement time begins. The power disablement time can be reset whenthe power enablement condition exists and/or the converter unit 102wakes up.

By ensuring that the power disablement time does not exceed thepredetermined power disablement time threshold, the converter unit 102can periodically monitor the charge status of the terminal 106. Thisprevents the terminal 106 from being fully charged, having the chargingof the terminal 106 be disabled, and then having the terminal 106 bedrained of its charge.

By detecting power enablement conditions, the converter unit 102 cananticipate when power consumption is necessary and/or will perform ameaningful function. This can reduce any inconvenience or impact for auser through the power consumption saving function of the batterycharger 100.

As seen in FIG. 2, the converter unit 102 can also include a terminalinput 121, a shell 128, and an indicator 130. The cable 104 can beconnected, for example, to the terminal input 121. The terminal input121 can be, for example, a universal serial bus (USB) input, an IEEE1394 interface, a proprietary input specific to a terminal, or any othertype of input that can be used to charge the rechargeable battery in theterminal and/or communicate with the converter unit 102. The shell 128can be, for example, a housing which can house the components of theconverter unit 102. The shell 128 can be formed from plastic, polymers,insulators, or any other type of material which can protect thecomponents of the converter unit 102.

The indicator 130 can be an indicator regarding the battery charger 100.The indicator 130 can indicate, for example, whether the converter unit102 is drawing power from the external power source, whether theconverter unit 102 is supplying power to the terminal 106, the charge ofthe battery 116, or any other type of information that may be useful toa user with regards to power consumption of the battery charger 102. Theindicator 130 can be, for example, a light indicator. The indicator 130can receive power from the battery 116 and/or the external power sourcethrough the power switching unit 112, the power circuit 114, and/or thepower input 118.

In one embodiment, the indicator 130 can display a first indication whenthe converter unit 102 is drawing power from the external power sourceand/or supplying the power to the terminal 106. The first indication canbe, for example, a first color. The indicator 130 can display a secondindication when the converter unit 102 is not drawing power from theexternal power source and/or not supplying power to the terminal 106.The second indication can be, for example, a second color or noindication at all. The indicator 130 can display a third indication whenthe converter unit 102 is not drawing power from the external powersource, but is supplying power to the terminal 106. The third indicationcan be, for example, a third color or no indication at all.

Circuit diagrams of the converter unit 102 according to an embodiment ofthe present invention can be seen, for example, in FIGS. 4-7. As seen inFIG. 4, the terminal 106 can be connected to an input 138 or an input140. The input 138 and the input 140 can be, for example, an input wherethe terminal 106 is connected to the battery charger 100 and/or theconverter unit 102. For example, the cable 104 can be plugged into theinput 138 and/or the input 140. The inputs 138 and 140 can be connectedto pins 2 and 3 of a connection 142 through the lines 144 and 146,respectively. The inputs 138 and 140 can be connected to the pins 6 and7 of the connection 142 through the lines 172 and 174, respectively.

As seen in FIG. 5, the pins 2 and 3 of the connection 142 can be used bya sensor 149 to detect whether the terminal 106 is connected to theconverter unit 102 or not. The sensor 149 can detect, for example, acapacitance of the terminal 106 using the pins 2 and 3. The sensor 149can also detect, for example, a capacitance of the cable 104 using thepins 2 and 3. The load monitor circuit 110 (FIG. 1) can include, forexample, the sensor 149.

As seen in FIGS. 5 and 6, the sensor 149 can transmit informationregarding the terminal 106 to a microprocessor 156 using a voltage formicrocontroller unit (“Vmcu”) signal, a wakeup signal, a serial dataaccess (“SDA”) signal, and/or a serial clock line (“SCL”) signal. Themicrocontroller 108 in FIG. 1 can include and/or correspond, forexample, to the microprocessor 156. The information can include, forexample, a capacitance of the terminal 106, a capacitance of the cable104, whether the terminal 106 is connected, and/or whether the cable 104has been touched.

As seen in FIG. 6, the microprocessor 156 receives the Vmcu signal, thewakeup signal, the SDA signal, and/or the SCL signal, and determineswhether the terminal 106 is connected to the converter unit 102 and/orthe battery charger 100. Referring to FIGS. 4 and 6, if the terminal 106is connected to the converter unit 102 and/or the battery charger 100,the microprocessor 156 detects a voltage and/or current of the terminal106 using the pins 6 and 7 of the connection 142. As previously noted,the pins 6 and 7 are connected to the inputs 138 and 140, which areconnected to the terminal 106. The pins 6 and 7 can transmit the signalsVusb1 and/or Vusb2. The microprocessor 156 can also determine the chargetime of the terminal 106, and whether the charge time exceeds thepredetermined charge time threshold. The microprocessor 156 can thendetermine whether a power enablement condition or a power disablementcondition has occurred.

As seen in FIGS. 6 and 7, the microprocessor 156 can send instructions,for example, to a microprocessor 160 using a LED1 signal and/or a LED2signal based on whether the power enablement condition or the powerdisablement condition has occurred. Based on the instructions from themicroprocessor 156, the microprocessor 160 can connect or disconnectpins in a relay 161. The latched relay 112 in FIG. 1 can include, forexample, the microprocessor 160 and/or the relay 161. In one embodiment,when the pins 2 and 3 in the relay 161 are disconnected, the lines 148and 154 do not form a complete circuit and no current flows through thelines 148 and 154. The pins 2 and 3 can be disconnected, for example,when the power disablement condition occurs. The switch 119 cancorrespond, for example, to the pins 2 and 3.

As seen in FIGS. 4 and 7, the lines 148 and 154 are connected to thepins 1 and 4 in the connection 152. In one embodiment, the lines 148 anda line 150 are lines which correspond to a main voltage input, such asthe main voltage input 118 in FIG. 1. As previously noted, the mainvoltage input 118 is connected to an external power source. When thelines 148 and 154 are disconnected and no current flows through them, nocurrent flows through the line 150 either since the line 150 requirescurrent to flow through the lines 148 and 154 to complete a circuit.Thus, during the power disablement condition, no current flows to theconverter unit 102 and the battery charger 100 does not draw power fromthe external power source. 100631 During the power enablement condition,the lines 148 and 154 are connected, enabling the lines 148, 154, and150 to complete a circuit. This allows power to flow to the converterunit 102 using the lines 148, 154, and/or the lines 150. As can be seenin FIG. 4, power flowing through the lines 148, 154, and/or the lines150 also reaches the terminal 106 through the inputs 138, 140, and/orthe connection 142. Furthermore, as seen in FIGS. 4 and 6, the currentflowing to the terminal 106 through the inputs 138 and 140 are monitoredby diodes 164, 166, 168, and 170 using the pins 6 and 7 and the signalsVusb1 and Vusb2 for the connection 142.

Referring back to FIG. 7, when the pins 6 and/or 7 are disconnected fromthe relay 161, they do not form a complete circuit for the battery 162and no current flows to the battery 162 or the microprocessor 163. TheVchg line connected to pin 7 is connected to a microprocessor 163 asshown in FIG. 6. The microprocessor 163 can monitor an energy level ofthe battery 162. The battery 162 can be, for example, a rechargeablebattery, a supercap, a solar cell, renewable energy devices, and/or anyother type of energy storage device. In FIG. 1, the battery monitor andcharging circuit 114 can include, for example, the microprocessor 163,while the battery 116 can correspond to the battery 162.

As seen in FIG. 6, the microprocessor 163 can send information regardingthe battery 162 to the microprocessor 156. The microprocessor 163 caninclude, for example, information regarding the energy level of thebattery 162. When the energy level of the battery 162 is above apredetermined energy threshold, the microprocessor 156 can instruct themicroprocessor 160 to disconnect the pins 6 and 7. Thus, even when poweris flowing from the external power source to the terminal 106, thebattery 162 will not be charged.

However, when the energy level of the battery 162 is below apredetermined energy threshold, the microprocessor 156 can instruct themicroprocessor 160 to connect the pins 6 and 7 in the relay 161 and theline Vchg and the line to the battery 162. In one embodiment, the pin 8can also be disconnected. The microprocessor 160 can also instruct themicroprocessor 160 to connect the pins 2 and 3 and the lines 148 and thelines 154 enabling the power to flow from the external power source tothe converter unit 102 and the battery 162.

In one embodiment, the present invention is a process as seen in FIG. 8.In Step S802 detection of whether a terminal 106 adaptor is electricallyconnected to a converter unit is performed. For example, the loadmonitor circuit 110 can detect whether the terminal 106 is connected tothe converter unit 102. In Step S804, a voltage of the terminal 106 isdetected. For example, the microcontroller 108 detects a voltage of theterminal 106. In Step S806, a charge time of the terminal 106 isdetected. For example, the microcontroller 108 can detected the chargetime using the load monitor circuit 110.

As seen in FIGS. 6 and 7, the converter unit 102 can also includeoptional reset switches. Furthermore, additional optional components arealso shown in FIGS. 4-7, which can be removed or substituted fordifferent components. Also, additional components may also be added tothe converter unit 102.

In Step S808, a power disablement condition is detected. For example,the microcontroller 108 can detect and determine whether the powerdisablement condition has occurred or not. In Step S810, reception ofpower from an external power source is disabled when the powerdisablement condition is detected. For example, when the powerdisablement condition is detected, the microcontroller 108 instructs thelatched relay 112 to disconnect the switch 119. In Step S812, the supplyof power to the terminal 106 is disabled. For example, by disconnectingthe switch 119, the converter unit 102 does not receive power and thusno power is supplied to the terminal 106.

In Step S814, a power enablement condition is detected. For example, themicrocontroller 108 can detect the power enablement condition. In StepS816 when the power enablement condition is detected, reception of powerfrom an external source is enabled. For example, when the powerenablement condition is detected by the microcontroller 108, themicrocontroller 108 instructs the latched relay 112 to connect theswitch 119. In Step S818, when the power enablement condition isdetected, supply of power to the terminal 106 is enabled. For example,when the switch 119 is connected, power flows from the external powersource to the converter unit 102 and from the converter unit 102 to theterminal 106.

The various illustrative logical blocks, units, modules, and circuitsdescribed in connection with the examples disclosed herein may beimplemented or performed with a general purpose processor, a digitalsignal processor (DSP), an application specific integrated circuit(ASIC), a field programmable gate array (FPGA) or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general purpose processor may be a microprocessor,but in the alternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

The steps of a method or algorithm described in connection with theexamples disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.Furthermore the method and/or algorithm need not be performed in theexact order described, but instead may be varied. A software module mayreside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROMmemory, registers, hard disk, a removable disk, a CD-ROM, or any otherform of storage medium known in the art. An exemplary storage medium iscoupled to the processor such that the processor can read informationfrom, and write information to, the storage medium. In the alternative,the storage medium may be integral to the processor. The processor andthe storage medium may reside in an Application Specific IntegratedCircuit (ASIC). The ASIC may reside in a wireless modem. In thealternative, the processor and the storage medium may reside as discretecomponents in the wireless modem.

The previous description of the disclosed examples is provided to enableany person of ordinary skill in the art to make or use the disclosedmethods and apparatus. Various modifications to these examples will bereadily apparent to those skilled in the art, and the principles definedherein may be applied to other examples without departing from thespirit or scope of the disclosed method and apparatus. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive and the scope of the invention is, therefore,indicated by the appended claims rather than by the foregoingdescription. All changes which come within the meaning and range ofequivalency of the claims are to be embraced within their scope.

What is claimed is:
 1. An electric charge cutoff device for deliveringpower to a terminal, comprising: a housing; a terminal adaptorconnectable to the terminal; a cable for extending from the housing andconnected to the terminal adaptor; a power connector plug connected tothe housing and configured to receive power from a power source externalto the housing; a sensor circuit positioned within the housing and forelectrically coupling to the cable, and configured to detect a variationin a capacitance of the cable; a latched relay positioned within thehousing and electrically coupled to the power connector plug andconfigured to electrically couple to the terminal adaptor, andconfigured to disable reception of power by the power connector plugfrom the power source in response to the sensor circuit detecting thevariation in the capacitance of the cable; and a renewable energy sourcepositioned within the housing and electrically coupled to the sensorcircuit, and configured to provide power to the sensor circuit whenreception of power by the power connector plug from the power source isdisabled.
 2. The electric charge cutoff device of claim 1, wherein thecable is configured such that the variation in the capacitance of thecable is caused by the terminal adaptor being disconnected from theterminal.
 3. The electric charge cutoff device of claim 1, furthercomprising a microcontroller electrically coupled to the sensor circuitand the latched relay, and configured to send a signal to the latchedrelay indicating that the sensor circuit detected the variation in thecapacitance of the cable.
 4. The electric charge cutoff device of claim3, wherein the microcontroller is configured to send a signal to thelatched relay indicating that the latched relay is to enable receptionof power by the power connector plug from the power source.
 5. Theelectric charge cutoff device of claim 4, wherein the microcontroller isconfigured to send the signal to the latched relay indicating that thelatched relay is to enable reception of power by the power connectorplug in response to the sensor circuit detecting a variation in thecapacitance of the cable.
 6. The electric charge cutoff device of claim3, wherein the renewable energy source is electrically coupled to themicrocontroller and is configured to provide power to themicrocontroller when reception of power by the power connector plug fromthe power source is disabled.
 7. The electric charge cutoff device ofclaim 1, wherein the renewable energy source is a rechargeable battery.8. The electric charge cutoff device of claim 7, further comprising abattery monitor electrically coupled to the rechargeable battery andconfigured to determine a charge level of the rechargeable battery. 9.The electric charge cutoff device of claim 8, wherein the batterymonitor is configured to cause the latched relay to enable reception ofpower by the power connector plug from the power source for delivery tothe rechargeable battery in response to the charge level detected by thebattery monitor.
 10. A charger for delivering power to a battery of aterminal, comprising: a housing; a terminal adaptor connectible to theterminal; a cable for extending from the housing and connected to theterminal adaptor, and configured such that a capacitance of the cablevaries in response to the terminal adaptor being disconnected from theterminal; a power connector plug connected to the housing and configuredto receive power from a power source external to the housing; a sensorcircuit positioned within the housing and for electrically coupling tothe cable, and configured to detect a variation in the capacitance ofthe cable in response to the terminal adaptor being disconnected fromthe terminal; and a switch positioned within the housing andelectrically coupled to the power connector plug and configured toelectrically couple to the terminal adaptor, and configured to disablereception of power by the power connector plug from the power source inresponse to the sensor circuit detecting the variation in thecapacitance of the cable.
 11. The charger of claim 10, furthercomprising a microcontroller electrically coupled to the sensor circuitand the switch, and configured to send a signal to the switch indicatingthat the sensor circuit detected the variation in the capacitance of thecable.
 12. The charger of claim 11, wherein the microcontroller isconfigured to send a signal to the switch indicating that the switch isto enable reception of power by the power connector plug from the powersource.
 13. The charger of claim 12, wherein the sensor circuit isconfigured to detect a variation in the capacitance of the cable inresponse to the terminal adaptor being connected to the terminal. 14.The charger of claim 13, wherein the microcontroller is configured tosend the signal to the switch indicating that the switch is to enablereception of power by the power connector plug in response to theterminal adaptor being connected to the terminal.
 15. The charger ofclaim 10, further comprising a renewable energy source positioned withinthe housing and configured to provide power to the sensor circuit whenreception of power by the power connector plug from the power source isdisabled.
 16. The charger of claim 15, further comprising a batterymonitor electrically coupled to the renewable energy source andconfigured to determine a power level of the renewable energy source,and configured to cause the switch to enable reception of power by thepower connector plug from the power source for delivery to the renewableenergy source in response to the power level detected by the batterymonitor.
 17. A method for disabling power to a converter unitcomprising: detecting, using a sensor circuit, a variation in acapacitance of a cable that extends from a housing of the converterunit, the sensor circuit being positioned within the housing; disabling,using a latched relay, reception of power into the housing from anexternal power source when the variation in the capacitance is detected,the latched relay being positioned within the housing; and powering thesensor circuit with a renewable energy source when the power is disabledfrom being received into the housing, the renewable energy source beingpositioned within the housing.
 18. The method of claim 17, wherein thevariation in the capacitance of the cable is caused by the cable beingdisconnected from a terminal that the cable is configured to deliverpower to.
 19. The method of claim 17, further comprising enabling, usingthe latched relay, reception of power into the housing from the externalpower source when a variation in the capacitance of the cable isdetected by the sensor circuit.
 20. The method of claim 19, furthercomprising supplying power to a battery of a terminal that the cable isconnected to when reception of power into the housing from the externalpower source is enabled.